Effect of a multimodal prevention strategy on dialysis-associated infection events in outpatients receiving haemodialysis: The DIPS stepped wedge, cluster-randomized trial

OBJECTIVES

Patients with haemodialysis catheters are susceptible to dialysis-associated infections, particularly bloodstream infections. There have been few systematic attempts to reduce this burden. Our study aimed to investigate the effect of a multimodal prevention strategy on dialysis-associated infection events (DAIE) among haemodialysis outpatients.

METHODS

A multicentre, stepped wedge, cluster-randomized controlled trial was done from October 2019 to September 2021. Outpatient dialysis facilities entered into the intervention phase in three randomly assigned clusters, at three predefined time points. The multimodal prevention strategy consisted of infection surveillance and hand hygiene (HH) compliance observation with active feedback and teaching aseptic procedures, and a patient flyer. The primary outcome was incidence rates of different DAIE, such as bloodstream infections, intravenous antimicrobial starts, and local access-site infections per 1000 dialysis. As secondary outcome, we analysed the HH compliance change.

RESULTS

A total of 43 haemodialysis outpatient facilities with 11 251 patients and 1 413 457 proceeded haemodialysis were included in the DIPS-trial. Incidence rates were 0.71 DAIE per 1000 dialysis (95% CI, 0.65-0.78) in the control and 0.31 (95% CI, 0.27-0.36) in the intervention group. The univariable analysis yielded an incidence rate ratio (IRR) of 0.44 (95% CI, 0.33-0.59) for DAIE. Especially in patients with a central venous catheter, we saw a significant decrease in DAIE in the intervention group (IRR 0.4; 95% CI, 0.28-0.58). The HH observation combined with feedback and intensified training, resulted in an increase of HH compliance from 58-65%.

DISCUSSION

A multimodal prevention strategy showed a significant preventive effect on DAIE among haemodialysis outpatients. This reduction also applied to bloodstream infections, especially in patients with a central venous catheter.

Central Venous Catheters for Hemodialysis-the Myth and the Evidence

Hemodialysis-central venous catheter (HD-CVC) insertion is a most often performed procedure, with approximately 80% of patients with end-stage kidney disease in the United States initiating kidney replacement therapy through a HD-CVC. Certain adverse events arising from HD-CVC placement, including catheter-related bloodstream infections (CR-BSIs), thrombosis, and central vein stenosis, can complicate the clinical course of patients and lead to considerable financial impact on the health care system. Medical professionals with different training backgrounds are responsible for performing this procedure, and therefore, comprehensive operator guidelines are crucial to improve the success rate of HD-CVC insertion and prevent complications. In this review article, we not only discuss the basic principles behind the use of HD-CVCs but also address frequently asked questions and myths regarding catheter asepsis, length selection, tip positioning, and flow rate assessment.

Dialysis Vascular Access: Where do Tunneled Catheters Stand? - A Single-Center Experience

Introduction

Tunneled cuffed catheters (TCC) provides a short and intermediate-term access solution for dialysis patients who fail to get an arteriovenous fistula (AVF). They are associated with high morbidity and mortality along with high rates of infectious complications.

Methods

We present a single-center prospective cohort of 159 TCCs inserted over one year. Patients were dialyzed in-hospital and in various peripheral dialysis units attached to the institute. The primary endpoint was catheter drop-out.

Results

The mean age of patients was 41.8 ± 16.9 years. The right internal jugular vein was the commonest site of TCC insertion (66%). The absence of suitable veins was the predominant reason for TCC insertion. The mean time to catheter drop-out was 134.4 ± 83.3 days (5-399 days). Death with a working catheter was the most common cause of catheter drop-out (22.6%). About 25% of catheters were lost to catheter-related bloodstream infections (CRBSI), either alone or as overlap with poor flow. CRBSI rates were 3.74 episodes per 1000 catheter-days. No difference in survival between the staggered tip and split-tip catheters was found.

Conclusions

With the advent of the "hub and spoke" model for dialysis in the public sector healthcare, TCCs are suboptimal with regards to patient and catheter survival, with high infection rates. It must be regarded as a temporary solution and AVF creation should be prioritized.

In Vitro and In Vivo Activity of a Novel Catheter Lock Solution against Bacterial and Fungal Biofilms

Central-line-associated bloodstream infections are increasingly recognized to be associated with intraluminal microbial biofilms, and effective measures for the prevention and treatment of bloodstream infections remain lacking. This report evaluates a new commercially developed antimicrobial catheter lock solution (ACL), containing trimethoprim (5 mg/ml), ethanol (25%), and calcium EDTA (Ca-EDTA) (3%), for activity against bacterial and fungal biofilms, using in vitro and in vivo (rabbit) catheter biofilm models. Biofilms were formed by bacterial (seven different species, including vancomycin-resistant Enterococcus [VRE]) or fungal (Candida albicans) species on catheter materials. Biofilm formation was evaluated by quantitative culture (CFU) and scanning electron microscopy (SEM). Treatment with ACL inhibited the growth of adhesion-phase biofilms in vitro after 60 min (VRE) or 15 min (all others), while mature biofilms were completely inhibited after exposure for 2 or 4 h, compared to control. Similar results were observed for drug-resistant bacteria. Compared to the heparinized saline controls, ACL lock therapy significantly reduced the catheter bacterial (3.49 ± 0.75 versus 0.03 ± 0.06 log CFU/catheter; P = 0.016) and fungal (2.48 ± 1.60 versus 0.55 ± 1.19 log CFU/catheter segment; P = 0.013) burdens in the catheterized rabbit model. SEM also demonstrated eradication of bacterial and fungal biofilms in vivo on catheters exposed to ACL, while vigorous biofilms were observed on untreated control catheters. Our results demonstrated that ACL was efficacious against both adhesion-phase and mature biofilms formed by bacteria and fungi in vitro and in vivo.

Haemodialysis catheters in the intensive care unit

Ten to 15% of critically ill patients need renal replacement therapy (RRT) for severe acute kidney injury. The dialysis catheter is critical for RRT quality and efficiency. Catheters have several properties that must be optimized to promote RRT success. The distal tip has to be located in a high blood flow location, which means central venous territory. Therefore, catheters are mostly inserted into the right internal jugular vein or in femoral veins. External diameter should vary from 12 to 16 Fr in order to ensure adequate blood flow inside the catheter. Lumen shapes are theoretically designed to limit thrombotic risk with low turbulences and frictional forces against the internal wall. With low aspiration pressure, distal tip shape has to deliver sufficient blood flow, while limiting recirculation rate. Catheter material should be biocompatible. Despite in vitro data, no strong evidence supports the use of coated catheters in the ICU in order to reduce infectious risk. Antibiotic "lock" solutions are not routinely recommended. Ultrasound guidance for catheterization significantly decreases mechanical complications. Clinicians should select the optimal catheter according to patient body habitus, catheter intrinsic properties and RRT modality to be used.

A project to reduce the rate of central line associated bloodstream infection in ICU patients to a target of zero

Central venous catheters (CVCs) are life-saving and the majority of patients in intensive care units (ICUs) have them placed in order to receive medicine and fluids. However, the use of these catheters can result in serious bloodstream infections. The rate of Central Line Associated Blood Stream Infection (CLABSI) in Adult Intensive Care Units (ICUs) at King Abdulaziz Medical City Jeddah (KAMC-J) at the start of the project was 2.0/1000 line days in 2008. The Central Line (CL) Bundle by the Institute of Healthcare Improvement (IHI) was implemented at the same time with monitoring of compliance to the CL Bundle. The compliance to CL Bundle was very low at 37% in the same period. A multidisciplinary team was created to improve the compliance to the CL bundle which was expected to have an impact on the rate of CLABSI to achieve zero CLABSI events. The team continued to monitor and evaluate the progress on the compliance to the bundle as well as monitoring the CLABSI events using National Healthcare Safety Network diagnostic criteria. The real reduction in the rate of CLABSI was achieved in 2010 with 0.7/1,000 device days when the compliance to CL Bundle reached up to 98% in that year and 100% in the next two subsequent years. The project still continued and the rate continued to drop and the ultimate target of zero CLABSI was achieved in the year 2014 and maintained in the year 2015 with a sustained compliance of 100% to the CL Bundle. Successful implementation of CL Bundle can help in reducing the rates of CLABSI and achieving zero CLABSI events for a sustained period.

Clinical impact and cost-effectiveness of a central line bundle including split-septum and single-use prefilled flushing devices on central line-associated bloodstream infection rates in a pediatric intensive care unit

BACKGROUND

Central line-associated bloodstream infections (CLABSIs) are among the most frequent health care-associated infections. Central line bundle (CLB) programs are useful for reducing CLABSIs.

METHODS

A retrospective study was designed to compare 2 periods: the prebundle and bundle periods. We evaluated the impact of a CLB including implementation of split-septum (SS) devices and single-use prefilled flushing (SUF) devices in critically ill children.

RESULTS

During the prebundle period, the overall rate was 24.5 CLABSIs per 1,000 central line (CL) days, whereas after the initiation of the CLB, the CLABSIs per 1,000 CL days dropped to 14.29. In the prebundle period, the daily cost per patient with CL and CLABSI were $232.13 and $254.83 consecutively. In the bundle period, the daily cost per patient with CL and CLABSI were $226.62 and $194.28 consecutively. Compared with the period with no CLB, the CLB period, which included SUF and SS devices, resulted in more costs saving by lowering the daily total costs of patients and indirectly lowering total drug costs by decreasing antibacterial and more significantly antifungal drugs.

CONCLUSIONS

CLB programs including SS and SUF devices were found to be effective in decreasing the CLABSI rate and decreasing the daily hospital costs and antimicrobial drug expenditures in children.

The Effect of Multiple Concurrent Central Venous Catheters on Central Line–Associated Bloodstream Infections

Objective

The current central line–associated bloodstream infection (CLABSI) surveillance rate calculation does not account for multiple concurrent central venous catheters (CVCs). The presence of multiple CVCs creates more points of entry into the bloodstream, potentially increasing CLABSI risk. Multiple CVCs may be used in sicker patients, making it difficult to separate the relative contributions of multiple CVCs and comorbidities to CLABSI risk. We explored the relative impact of multiple CVCs, patient comorbidities, and disease severity on the risk of CLABSI.

Design

Case-control study.

Setting

A total of 197 case patients and 201 control subjects with a CVC inserted during hospitalization at a tertiary care academic medical center from January 1, 2008, to December 31, 2010.

Methods

Multiple CVCs was the exposure of interest; the primary outcome was CLABSI. Multivariable logistic regression was conducted to estimate odds ratios (ORs) and 95% confidence intervals (CIs) describing the association between CLABSI and multiple CVCs with and without controlling for Acute Physiology and Chronic Health Evaluation (APACHE) II and Charlson comorbidity index (CCI) scores as measures of disease severity and patient comorbidities, respectively.

Results

Patients with multiple CVCs (n = 78) showed a 4.2 (95% CI, 2.2–8.4) times greater risk of CLABSI compared with patients with 1 CVC after adjusting for CLABSI risk factors. When including APACHE II and CCI scores, multiple CVCs remained an independent risk factor for CLABSI (OR, 3.4 [95% CI, 1.7–6.9]).

Conclusions

Multiple CVCs is an independent risk factor for CLABSI even after adjusting for severity of illness. Adjustment for this risk may be necessary to accurately compare rates between hospitals.

Infect Control Hosp Epidemiol 2014;35(9):1140-1146

Limitations of Murine Models for Assessment of Antibody-Mediated Therapies or Vaccine Candidates against Staphylococcus epidermidis Bloodstream Infection

Staphylococcus epidermidis is normally a commensal colonizer of human skin and mucus membranes, but, due to its ability to form biofilms on indwelling medical devices, it has emerged as a leading cause of nosocomial infections. Bacteremia or bloodstream infection is a frequent and costly complication resulting from biofilm fouling of medical devices. Our goal was to develop a murine model of S. epidermidis infection to identify potential vaccine targets for the prevention of S. epidermidis bacteremia. However, assessing the contribution of adaptive immunity to protection against S. epidermidis challenge was complicated by a highly efficacious innate immune response in mice. Naive mice rapidly cleared S. epidermidis infections from blood and solid organs, even when the animals were immunocompromised. Cyclophosphamide-mediated leukopenia reduced the size of the bacterial challenge dose required to cause lethality but did not impair clearance after a nonlethal challenge. Nonspecific innate immune stimulation, such as treatment with a Toll-like receptor 4 (TLR4) agonist, enhanced bacterial clearance. TLR2 signaling was confirmed to accelerate the clearance of S. epidermidis bacteremia, but TLR2(-/-)mice could still resolve a bloodstream infection. Furthermore, TLR2 signaling played no role in the clearance of bacteria from the spleen. In conclusion, these data suggest that S. epidermidis bloodstream infection is cleared in a highly efficient manner that is mediated by both TLR2-dependent and -independent innate immune mechanisms. The inability to establish a persistent infection in mice, even in immunocompromised animals, rendered these murine models unsuitable for meaningful assessment of antibody-mediated therapies or vaccine candidates.

The bacterial colonization in tunneled cuffed dialysis catheter and its effects on residual renal function in incident hemodialysis patients

BACKGROUND

The bacterial colonization of hemodialysis catheter occurs frequently and reaches to the catheter-related bloodstream infections (CRBSIs). We hypothesized bacterial colonization promotes inflammation and that might be associated with renal outcome. The aim of this study was to investigate the colonization status for tunneled cuffed dialysis catheter (TCC) and the factors for contributing to the catheter colonization and explore whether bacterial colonization would be related with declining of residual renal function (RRF).

METHODS

115 patients who received TCC removal operation and underwent catheter tip culture from January 2005 to June 2014 were enrolled. The follow-up data such as urine output (UO), time to anuria and patients' survival were collected from the patients or their family members by telephone in June, 2014.

RESULTS

There were nineteen patients (16.5 %, 19/115) with positive tip culture (colonization group). In the analysis of demographic and biochemical parameters, there were no significant differences between both groups. Fifty of all the subjects responded to the telephone survey and ten patients (20.0 %, 10/50) belonged to colonization group. The monthly decreasing rate of UO was significantly more rapid in colonization group (p = 0.001). The survival analysis showed that colonization group had worse estimated anuria-free survival than non-colonization group (p < 0.001). In multivariate cox regression, bacterial colonization of TCC was an independent factor influencing the loss of RRF (HR 4.29, 95 % CI: 1.905-9.683, p ≤ 0.001).

CONCLUSIONS

Bacterial colonization of TCC was associated with rapid loss of RRF.

Maintaining safety in the dialysis facility

Errors in dialysis care can cause harm and death. While dialysis machines are rarely a major cause of morbidity, human factors at the machine interface and suboptimal communication among caregivers are common sources of error. Major causes of potentially reversible adverse outcomes include medication errors, infections, hyperkalemia, access-related errors, and patient falls. Root cause analysis of adverse events and "near misses" can illuminate care processes and show system changes to improve safety. Human factors engineering and simulation exercises have strong potential to define common clinical team purpose, and improve processes of care. Patient observations and their participation in error reduction increase the effectiveness of patient safety efforts.

Usefulness of endoluminal catheter colonization surveillance cultures to reduce catheter-related bloodstream infections in hemodialysis

BACKGROUND

To evaluate the use of surveillance cultures (SCs) to prevent catheter-related bloodstream infections (CRBSIs) in asymptomatic hemodialysis (HD) patients.

METHODS

In 2011-2012, we conducted a prospective study of HD patients with tunneled cuffed central venous catheters (TCCs). Colonization of the catheter lumen was assessed every 15 days by inoculating ~5 mL endoluminal blood into aerobic culture bottles. Individual patients were triaged based on SC results: group 1 (negative); group 2 (coagulase-negative Staphylococcus [CoNS] with time-to-positivity (TTP) >14 hours); group 3 (CoNS with TTP ≤14 hours); and group 4 (any microorganism other than CoNS and any TTP).

RESULTS

We studied 104 patients (129 TCCs). Median follow-up was 262.5 days (interquartile range [IR], 135.0-365.0). A total of 1,734 SCs were collected (median, 18 per patient; IR, 10.0-24.0), of which 1,634 (94.2%) were negative (group 1) and 100 (5.8%) were positive (group 2: 79; group 3: 12, group 4: 9). In groups 2 and 3, 19 TCCs required antibiotic lock therapy (ALT). In group 4, all patients received intravenous therapy and ALT. Under this protocol, there were 0.27 episodes of CRBSI per 1,000 catheter days compared with 1.65 (P < .001) prior to its implementation.

CONCLUSION

SCs based on easily accessible samples proved useful in triaging HD patients at a high risk of infection.

The impact of central line insertion bundle on central line-associated bloodstream infection

BACKGROUND

Knowledge about the impact of each central line insertion bundle on central line-associated bloodstream infection (CLABSI) is limited.

METHODS

A quality-improvement intervention, including education, central venous catheter (CVC) insertion bundle, process and outcome surveillance, have been introduced since March 2013. Outcome surveillances, including CLABSI per 1,000 catheter-days, CLABSI per 1,000 inpatient-days, and catheter utilization rates (days of catheter use divided by total inpatient-days), were measured. As a baseline measurement for a comparison, we retrospectively collected data from March 1, 2012 to December 31, 2012.

RESULTS

During this 10-month period, there were a total of 687 CVC insertions, and 627 (91.2%) insertions were performed by intensivists. The rate of CLABSI significantly declined from 1.65 per 1000 catheter-day during the pre-intervention period to 0.65 per 1000 catheter-day post-intervention period (P=0.039). CLABSI more likely developed in subjects in which a maximal sterile barrier was not used compared with subjects in which it was used (P=0.03). Moreover, CVC inserted by non-intensivists were more likely to become infected than CVC inserted by intensivists (P=0.010).

CONCLUSIONS

This multidisciplinary infection control intervention, including a central line insertion care bundle, can effectively reduce the rate of CLABSI. The impact of different care bundle varies, and a maximal sterile barrier precaution during catheter insertion is an essential component of the care line insertion bundle.

Antibodies to PhnD inhibit staphylococcal biofilms

Biofilm formation on central lines or peripheral catheters is a serious threat to patient well-being. Contaminated vascular devices can act as a nidus for bloodstream infection and systemic pathogen dissemination. Staphylococcal biofilms are the most common cause of central-line-associated bloodstream infections, and antibiotic resistance makes them difficult to treat. As an alternative to antibiotic intervention, we sought to identify anti-staphylococcal biofilm targets for the development of a vaccine or antibody prophylactic. A screening strategy was devised using a microfluidic system to test antibody-mediated biofilm inhibition under biologically relevant conditions of shear flow. Affinity-purified polyclonal antibodies to target antigen PhnD inhibited both Staphylococcus epidermidis and S. aureus biofilms. PhnD-specific antibodies blocked biofilm development at the initial attachment and aggregation stages, and deletion of phnD inhibited normal biofilm formation. We further adapted our microfluidic biofilm system to monitor the interaction of human neutrophils with staphylococcal biofilms and demonstrated that PhnD-specific antibodies also serve as opsonins to enhance neutrophil binding, motility, and biofilm engulfment. These data support the identification of PhnD as a lead target for biofilm intervention strategies performed either by vaccination or through passive administration of antibodies.

Survey of infection control practices in hemodialysis units: preventing vascular access-associated bloodstream infections

OBJECTIVE

Despite surveillance, the Quebec Healthcare-Associated Infections Surveillance Program saw no improvement in vascular access-associated bloodstream infections in hemodialysis (HD). We aimed to determine the infection control measures recommended and implemented in Quebec's HD units, compliance of local protocols to infection control practice guidelines, and reasons behind the low prevalence of arteriovenous fistulas.

METHODS

An online survey was elaborated on the basis of the Centers for Disease Control and Prevention (CDC) and National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines. The questionnaire was validated (construct, content, face validity, and reliability) and sent to all HD units in Quebec (n = 40). Results were analyzed using descriptive statistics, linear regression, and Poisson regression.

RESULTS

Thirty-seven (93%) of 40 HD units participated. Thirty (94%) of the 32 centers where central catheters are inserted have written insertion protocols. Compliance with practice guidelines is good, except for full-body draping during catheter insertion (79%) and ointment use at insertion site (3%). Prevention measures for catheter maintenance are in accordance with guidelines, except for skin disinfection with at least 0.5% chlorhexidine and 70% alcohol (67% compliance) and regular antiseptic ointment use at the insertion site (3%). Before fistula cannulation, skin preparation is suboptimal; forearm hygiene is performed in only 61% of cases. Several factors explain the low rate of fistulas, including patient preference (69%) and lack of surgical resources (39%; P = .01).

CONCLUSIONS

Improvement in standardization of care according to practice guidelines is necessary. Fistula rate could be increased by improving access to surgical resources and patient education. Strategies are now being elaborated to address these findings.

Patients’ perceptions of hemodialysis catheter care practices at home before and after eliminating a protective dressing and implementing a showering protocol

Catheter-related bloodstream infection is a major cause of patient morbidity, mortality, and cost for patients undergoing hemodialysis. Healthcare personnel have control over central venous catheter care in the healthcare setting, but patient practices in the home environment may play a role in catheter-related infections. This qualitative study investigated hemodialysis catheter-related care in the home environment and developed an understanding of the experience of catheter care for which patients were responsible. The themes that emerged from the data were perceptions of catheter care practices, feelings of freedom, fear, a few frustrations, and patient empowerment. The findings from the analysis provide a snapshot of the variability in catheter care practices in the home as self-reported by the patients undergoing hemodialysis before and after involvement in a protocol that eliminated the dressing over the catheter insertion site and taught participants ways to care for the site during showering. The data may be used to inform care that decreases catheter-related infections, to describe the impact of showering on catheter-related infections, and to influence patient adherence to best practices through enhanced patient empowerment, comfort, control, and perceptions of personal hygiene.

Impact of a multidimensional infection control approach on central line-associated bloodstream infections rates in adult intensive care units of 8 cities of Turkey: findings of the International Nosocomial Infection Control Consortium (INICC)

Background

Central line-associated bloodstream infections (CLABs) have long been associated with excess lengths of stay, increased hospital costs and mortality attributable to them. Different studies from developed countries have shown that practice bundles reduce the incidence of CLAB in intensive care units. However, the impact of the bundle strategy has not been systematically analyzed in the adult intensive care unit (ICU) setting in developing countries, such as Turkey. The aim of this study is to analyze the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional infection control approach to reduce the rates of CLAB in 13 ICUs of 13 INICC member hospitals from 8 cities of Turkey.

Methods

We conducted active, prospective surveillance before-after study to determine CLAB rates in a cohort of 4,017 adults hospitalized in ICUs. We applied the definitions of the CDC/NHSN and INICC surveillance methods. The study was divided into baseline and intervention periods. During baseline, active outcome surveillance of CLAB rates was performed. During intervention, the INICC multidimensional approach for CLAB reduction was implemented and included the following measures: 1- bundle of infection control interventions, 2- education, 3- outcome surveillance, 4- process surveillance, 5- feedback of CLAB rates, and 6- performance feedback on infection control practices. CLAB rates obtained in baseline were compared with CLAB rates obtained during intervention.

Results

During baseline, 3,129 central line (CL) days were recorded, and during intervention, we recorded 23,463 CL-days. We used random effects Poisson regression to account for clustering of CLAB rates within hospital across time periods. The baseline CLAB rate was 22.7 per 1000 CL days, which was decreased during the intervention period to 12.0 CLABs per 1000 CL days (IRR 0.613; 95% CI 0.43 – 0.87; P 0.007). This amounted to a 39% reduction in the incidence rate of CLAB.

Conclusions

The implementation of multidimensional infection control approach was associated with a significant reduction in the CLAB rates in adult ICUs of Turkey, and thus should be widely implemented.